CHIP and HIP text demo and font

[Synthpopalooza]

I've managed to design a text font for the HIP 0 and CHIP 0 software modes, and have done up a program which shows what these look like. The font also contains some graphics characters as well. Again, this is in TurboBASIC, although easily adaptable for normal Atari BASIC.

 

 

When you are designing fonts for this mode, you are basically working with 2 characters per letter at a 6x8 grid, with the luminance mask underlaying the hue mask. You have to use a 2-pixel wide resolution for the letters and 2-character wide resolution, or the letters won't display properly. The result is 144 colors displayable at a virtual Graphics 0 resolution.

 

The second picture is in the CHIP 0 (0.10/0.11) mode ... in this one, I am using mode 10 as the luminance mask, but still using the same font.

 

The font file that is included needs to reside on H2: or you can change it in the turbobasic file.

 

EDIT: I just noticed an error in the basic listing, in line 70, it should read POKE 1027,CHBAS2/256 (not 10271).

hip-chipdemo.zip

Edited October 12, 2009 by Synthpopalooza

[Synthpopalooza]

I've now done up a font specifically for the CHIP 0 (0.10/0.11) mode. The palette settings I am using for mode 10 are grayscale. Mode 10 provides the luminance in this case, while mode 11 provides the hues. This mode displays between 128-144 colors at a pixel-shifted resolution of 160 pixels across.

 

chipdemo.zip

Edited October 12, 2009 by Synthpopalooza

[Allas]

Could you send the test with autobooteable DOS with TurboBasic and test files on it?

Edited October 14, 2009 by Allas

[Synthpopalooza]

Could you send the test with autobooteable DOS with TurboBasic and test files on it?

 

Ok, here is an ATR which contains both test demos for CHIP and HIP modes, and the respective fonts. I also went ahead and included the most recent beta version of the ICE editor, which has now fixed all the bugs when displaying character pixels in the grid. I've used this to design the fonts.

 

Make sure when you boot this ATR, that you disable BASIC. Also, this ATR will only work with XL/XE (Turbobasic, plus requires GTIA chip) ... keep in mind though, this code can be easily modified to work under normal Atari BASIC, as all you are doing is loading a double font, reserving memory below ramtop, and setting a DLI on one of the skipped scan lines (before the actual display begins) and causing the DLI to flip the screen with the CHBAS and GTIPRIOR registers, the values of which are being read from a table at $0400. The code can also be modified to work inside a VBI rather than a DLI, you would just need to use the shadow registers (756 and 623 decimal) instead of the hardware ones.

font.zip

Edited October 14, 2009 by Synthpopalooza

[Allas]

I think those type of text mode flicks a lot on PAL monitors, but works fine on a NTSC.

However, taking care about mixing with the same luminance will reduce the flickering drastically.

 

I don't see the program listing, but it seems the registers change on any position of screen. This should be on a VBI toi get a better screen mixing.

[Synthpopalooza]

I think those type of text mode flicks a lot on PAL monitors, but works fine on a NTSC.

However, taking care about mixing with the same luminance will reduce the flickering drastically.

 

I don't see the program listing, but it seems the registers change on any position of screen. This should be on a VBI toi get a better screen mixing.

 

Yes, I think it is because PAL machines run at 1/50 cycles, while the NTSC runs at 1/60 and gives a faster refresh. And the two registers (CHBAS and GTIPRIOR) do change over the whole screen.

 

And also, when designing text, keeping the luminance within about 2 settings either way, does reduce the flicker.